1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one
3 * or more contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. The ASF licenses this file
6 * to you under the Apache License, Version 2.0 (the
7 * "License"); you may not use this file except in compliance
8 * with the License. You may obtain a copy of the License at
9 *
10 * http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing,
13 * software distributed under the License is distributed on an
14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15 * KIND, either express or implied. See the License for the
16 * specific language governing permissions and limitations
17 * under the License.
18 */
19 package org.apache.myfaces.shared_orchestra.renderkit;
20
21 import javax.faces.context.ExternalContext;
22 import javax.faces.context.FacesContext;
23 import java.util.Map;
24
25 /**
26 * @author Thomas Spiegl
27 */
28 public class ViewSequenceUtils {
29 private static final String SEQUENCE_PARAM = "jsf_sequence";
30
31 /**
32 * Increments view sequence by 1.
33 *
34 * @param facescontext
35 */
36 public static void nextViewSequence(FacesContext facescontext) {
37 ExternalContext externalContext = facescontext.getExternalContext();
38 Object sessionObj = externalContext.getSession(true);
39 synchronized (sessionObj) // synchronized to increase sequence if multiple requests
40 // are handled at the same time for the session
41 {
42 Map map = externalContext.getSessionMap();
43 Integer sequence = (Integer) map.get(SEQUENCE_PARAM);
44 if (sequence == null || sequence.intValue() == Integer.MAX_VALUE) {
45 sequence = new Integer(1);
46 }
47 else {
48 sequence = new Integer(sequence.intValue() + 1);
49 }
50 map.put(SEQUENCE_PARAM, sequence);
51 externalContext.getRequestMap().put(SEQUENCE_PARAM, sequence);
52 }
53 }
54
55 /**
56 * Returns current view sequence and sets current view sequence to Integer(1) if
57 * current sequence value is NULL.
58 *
59 * @param facescontext
60 * @return
61 */
62 public static Integer getViewSequence(FacesContext facescontext) {
63 Map map = facescontext.getExternalContext().getRequestMap();
64 Integer sequence = (Integer) map.get(SEQUENCE_PARAM);
65 if (sequence == null) {
66 sequence = new Integer(1);
67 map.put(SEQUENCE_PARAM, sequence);
68
69 synchronized (facescontext.getExternalContext().getSession(true)) {
70 facescontext.getExternalContext().getSessionMap().put(SEQUENCE_PARAM, sequence);
71 }
72 }
73 return sequence;
74 }
75
76
77 /**
78 * Current view sequence, may be NULL!
79 *
80 * @param context
81 * @return
82 */
83 public static Integer getCurrentSequence(FacesContext context) {
84 Map map = context.getExternalContext().getSessionMap();
85 return (Integer) map.get(SEQUENCE_PARAM);
86 }
87
88 }